There is no official word from Vauxhall, but it seems certain that an Astra-based convertible will be launched at the Paris Motor Show in September.

The latest rumour (of many) comes from industry website www.just-auto.com which says it will go into production in Poland in early 2013, and will feature a fabric roof, rather than a folding metal one. It will be based on the Astra GTC Coupe, which is certainly not a bad place to start: the GTC is a good-looking car and has a decent chassis.

Folding metal roofs are amazing pieces of engineering with ability to perform origami on themselves, but they are heavy and expensive. They also need a big boot into which they can fold, which compromises the styling: nearly all Astra/Focus type cars with such roofs have very big backsides. Given that these cars are principally fashion items, the styling problems do seem like a bit of an own-goal.

It is certainly encouraging that Vauxhall/Opel is continuing to invest in new models, despite the torrent of red ink flowing through the company. Earlier this week it announced a loss of $400 million (£250 million) in the last three months alone. The company is hoping that a combination of more attractive models and cost-cutting will bring it to profitability.